Stans Circulation CB7 Carbon-Rimmed Wheelset Holds True [Review]
In bike evaluations and press releases we regularly write in regards to the “carbon wheels” that an additional fancy bike comes with. The storied powers that these glued fibers maintain give the bike an elevated essence, and a value hike. In fact, there are only a few totally carbon fiber bicycle wheels on the earth. Manufacturers like Topolino, Madfiber, and Syncros have taken a crack at totally carbon hoops prior to now, with diversified success.
As lots of you understand, what we imply when writing “carbon wheels” is that the wheel system makes use of carbon rims. The spokes are strings of metal, nipples are aluminum or brass, bearings are metal or ceramic with metal races and plastic seals, axles are sometimes elongated metal or alloy cylinders, and most fashionable hub shells and freehub our bodies are fabricated from aluminum. From there, spoke lacing and butting, rim depth and width, bearing placement, and 300 different elements affect the best way a wheelset performs. The phrase “carbon wheelset” is shorthand for “it’s difficult.”
I just lately had the pleasure of testing Stans carbon-rimmed Flow CB7 wheelset on my Norco Torrent hardtail. For those who’re in a rush to skim the small print I’ll prevent a while. Priced at an affordable $1,399 this 1804g gravity wheelset is a worthwhile improve for riders who’re on the wheel improve hunt. The Circulation CB7 add the stiffness and precision you anticipate from carbon rims with out the proprietary construct spec and crack-ability that accompany a few of the competitors. In case you do handle to completely case one in all these rims, Stans affords an intensive guarantee and crash substitute to again up their sturdy design. Now for the particulars.
I’ll kick off by stating that I maintain excessive expectations of recent Stans No Tubes items. The corporate basically made mountain biking extra enjoyable with the arrival of their commemorated tubeless sealant virtually twenty years in the past. That’s a tricky act to observe.
The distinctive ingredient of the Crest CB7 wheelset is its rim form and up to date freehub physique. These are Stans first go at asymmetrical rims, and the tubeless compatibility and setup needed to be excellent. Asymmetrical rims have the spoke holes drilled barely to at least one facet to permit for even spoke lengths on each side regardless of the cassette and rotor placement — leading to a extra balanced and sometimes occasions stronger wheel construct.
The difficult bit for Stans was to design an asymmetrical rim with an inside bead seat or “ditch” that held the bead equally tight on both facet. They experimented with quite a lot of shapes to realize the Circulation CB7 type, the place the interior slopes reportedly take an equal quantity of air strain to lock the bead into place. That locking movement is essential for correct tubeless setup, and presumably extra essential to maintain the tire from “burping” or shedding air on laborious lateral compressions. Some asymmetrical rims can are inclined to burp extra simply on one facet than the opposite, and this was a component that the parents at Stans couldn’t settle for.
I mounted up a sturdy 1,000g set of Onza Aquila 29 x 2.4 tires on the Circulation CB7 rims that can be a part of an “Aaron Gwin Authorised” tire evaluate within the close to future. With a Nukeproof ARD insert within the rear tire and a wholesome dollop of Tyre Yogurt within the pair, the tires arrange as shortly and effortlessly as anticipated. After a number of months of scorching summer time testing, the Tyre Yogurt stays thick and fluid, and the corporate says it may be scooped into one other tire and used for the remainder of the season. Whereas I’m nonetheless completely satisfied to make use of Stans No Tubes sealant any day, it’s nice to see some newer corporations doing issues a little bit otherwise.
The ARD insert has some cuts the place it saved my rear tire, rim, and experience, but it surely doesn’t appear to be sopping up the sealant fairly but. I’ll positively depart or not it’s for the rest of the 12 months. With zero punctures in these tires to date, I’m greater than glad with how the sealant and insert have carried out.
Twenty-nine millimeters is inside the trade normal for gravity bike inside rim measurements as of late, and the majority of tire corporations are designing casings accordingly. The Aquila tread arrange good and sq. above the CB7 rims, with simply the correct quantity of corner-hugging curve.
I’ve had lower than favorable expertise with Stans Neo hubs prior to now. The units I’ve labored with by myself bikes and people of buddies’ would blow by means of bearings shortly and have been in any other case indistinguishable from a lot of the competitors. Whereas I haven’t ridden the wheels lengthy sufficient to really take a look at the bearing life, this new set is rolling easy and the bearings really feel clear regardless of being mounted on my rainy-day bike. The newest Neo freehub has a 3rd bearing to unfold the axle load, which ought to contribute to longer-lasting bearings all through.
|Worth||$1,399 (obtainable on-line at Worldwide Cyclery, Treefort Bikes, and Performance)|
|Weight||1804g in measurement 29″ with rim tape and valves put in|
|Advisable tire width||2.35 – 2.80″|
|Spokes||Sapim Drive Black 2.0/1.7/1.8 spokes with Safe Lock aluminum nipples|
|Freehub choices||SRAM XD, Shimano HG, Shimano MicroSpoline|
|Inner rim width||29mm|
|Max rider weight||250lbs (113 kilo)|
The up to date Neo Final Velocity Sync freehub system is a large enchancment. The six pawls work together with 72 factors of contact within the hub shell for a good 5° engagement. That’s a leap up from 10° with the unique Neo hubs. It’s noticeable any time a climb turns into technical sufficient that wonderful crank actions are essential to take care of ahead momentum. As compared, Shimano’s newest XTR freehub has 7.6° of engagement, so I’d say that the Neo is doing effectively for itself.
With out exception the Circulation CB7 rims have been good on their “no burp” tubeless assure. I’ve been working pretty low pressures at round 18-19PSI with these wheels so I may attempt to burp the tires on sideways compressions and crack the edges on stones. No Cube. The tires have learn the identical strain on the finish of each experience that they did originally, and the edges are crack-free and dead-true. The stiff rims maintain tight to the bead, locking it in on each side to maintain all the air and sealant the place it belongs.
Stans claims that their RiACT carbon rim building methodology creates a circle with 3X the lateral stiffness of their aluminum rims, whereas offering as much as 10mm of radial flex on impression. They state that “our carbon rims can deflect 7-10mm with out harm or pinch flatting,” and I’ve but to show them incorrect.
On the primary few rides, I had the sensation that the wheels have been too stiff. Harsh even. I quickly realized that the Torrent body is stiffer than different metal hardtails I’ve owned, and paired with the 37mm stanchioned Manitou Mezzer Pro fork I had merely over-stiffened the construct. I mounted the wheels on my full suspension bike they usually felt good. I’ve since swapped in a smaller 31.8mm handlebar on the hardtail and the vibrations calmed considerably. Once more, it’s not simply carbon rims. It’s a complete system.
Happily, the Circulation CB7 wheels maintain their lateral form affirmatively, it doesn’t matter what bike they’re on. Whether or not carving deep in a berm or hoping for traction throughout off-camber roots, the lateral stiffness provides helpful precision to the bike’s entrance finish. In comparison with the equally formed alloy DRC Bigfoot rims I used to be working on my full suspension setup beforehand, the CB7 offers the bike a extra correct cornering character. I’m able to maintain a line higher on unfastened and tough trails than I may on some aluminum hoops.
Whereas the CB7 wheels weren’t the principle wrongdoer in my overly inflexible bike setup, they do really feel rather less forgiving than another carbon rims I’ve examined. The distinction is refined. I discover it as a result of I get to experience 6-7 days per week on quite a lot of high-end wheels, however for most folk who get pleasure from trails on the weekend, these wheels will seemingly really feel precisely how they anticipate carbon circles to really feel.
My solely different criticism, which is equally minor, is that the freehub has began to pull barely and certain must be cleaned and re-greased. If I’m spinning a excessive cadence and cease swiftly I can really feel (and watch) a tug on the drivetrain because the freehub takes a little bit further time to cease spinning in lockstep with the wheel. Whereas this may ultimately occur with any freehub, it sometimes takes a full 12 months or two of using earlier than a drag-dragon reveals up and asks for a shower.
For the last word path using and enduro racing wheelset, I would favor an aluminum rim below the saddle and a carbon rim beneath the handlebar. With that combo, you get all the precision enhancing advantages up entrance the place the rim is significantly much less prone to break, and a extra pliable and forgiving rim out again that may sometimes be straightened out ought to or not it’s broken on impression. For anybody who agrees, Stans Circulation CB7 carbon rims can be found à la carte for $600.
We want to thank Stans No Tubes fr sending the Circulation CB7 wheelset over for evaluate.